Spike-tooth harrow.



No. 650,676. Patented May 29, I900. W. M. FRANK.

SPIKE TOOTH NARROW.

(Application filed Feb. 3, 1900.)

(No Model.)

, INVENTOR.

55 64 ATTORNEY.

WITNESSES.- $4756...-

m we

WILLIAM Mormon FRANK, 0F SPRINGFIELD, orno'.

SPIKE-TOOTH HARROW;

s'rnc'zrrcarxcn forming as of Letters was No. 650,676, dated ma 29,1900; Application filed February 3,1900. $e1ialN0=3,918. (No model.)

To all whom it may concern/.-

Be it known that I, WILLIAM' MONROE FRANK, of Springfield, county ofClark, and State of Ohio, have invented a certain new and usefulSpike-Tooth Harrow; and I do hereby declare that the following is afull, clear, and exact description thereof, reference being had to theaccompanying drawings,-in which like figures refer to like parts.

The object of this invention as herein disclosed is to provide practicaland economical means for attaching'spike harrow-teeth to harrows whoseframes are made of pipes or tubes, generally known as pipe-barrows orframe-bars, round or partially round. By securing the tooth to .the sideof the pipe the latter is in no wise weakened, and while it is not newto secure spike-teeth to the side of the frame-bar of a harrow means foreffectually securing such a tooth to the side of a pipe in pipe-barrowshas never been invented, so far as I am aware. Aside from the advantageabove mentioned of my invention another decided advantage consists inthe ability with my tooth-fastening to attach teeth of varying sizeswithout changing the harrowfasteners in any wise. In the means abovedescribed of inserting the tooth through the pipe vertically only onesize of tooth can be used withjthe same pipe or fasteners, and the sizeof such tooth must be relativelysmall, so as not to require such largeopenings through the pipe as to render it absolutely useless.

With my invention a half-inch or five-eighthinch or inch tooth can beattached to any pipe-harrow, as desired, and the strength of the framewill not be diminished or affected.

One feature of my invention also consists in the arrangement of clipswhereby great bearing-surface is provided, which when the clips areclamped together absolutely prevents the vertical movement of the teeth.Another advantage of such clip arrangement is their increased resistanceto the twisting movement of the teeth when under strain while the harrowis in use. Likewise the arrangement herein set forth prevents anylateral movement of .the teeth. All these advantages accrue from my saidinvention without anyincrease in the cost of manufacture. These, withthe other features of my invention, will more fully appear from theaccompanying drawings and the description following of one form ofdevice embodying my said invention, and the scope of said invention willbe understood from the claims following said description.

In the drawings herein shown to illustrate the nature of my invention,Figurel is a central vertical section through a pipe of a har- 6orow-frame and adjacent tooth-fastening, the tooth being centrally brokenaway. Fig. 2 is a plan of a section of a pipe of a harrowframe and atooth and fastening. Fig. 3 is an elevation of a section of a pipe of aharrow-frame with the fastener and the upper part of a tooth in place.Fig. 4 is ahorizontal cross-section of the fastening with a porti on ofthe pipe-frame shown in section and the tooth shown in plan. Fig. 5 isthe same section as is shown in Fig. 1, with the tooth removed.

Referring 'tothe details of the device herein shown for the purpose ofillustrating this invention, 1 is a pipe forming a part of the frame ofthe pipe-harrow. The general arrangement and construction ofpipe-harrows is well known to all acquainted with the art. Pipes form aharrow frame of unusual strength when compared with its weight, and Sotherefore it is much in favor, because of its convenience in use, forharrows while in actual use and also in transportation must be handledconsiderably.

2 represents a spike harrow-tooth like those now in general use, beingsmaller and sharp as compared with the old-fashioned iron spiketooth, sothat they enter the ground with less weight than the old teeth that werelarger and blunter. 0

I herein show a pair of clips--an inside clip 3 and an outside clip4=-'-whose adjacent faces are provided with vertical rectangulargrooves, as seen in Fig. 5 and indicated in Figs. 2 and 4, to receivethe harrow-tooth. 5 As seen in Figs. 2 and 4:, one angular half of thetooth fits in the groove in the inside clip 3 and the other half of thetooth in the groove of the outer clip 4:. These grooves extend for thewhole vertical length of the clips and combined practically surround thetooth, and therefore present a very extensive frictional surface-bearingagainst the tooth when they are clamped together. Said clips are clampedtogether, and also against the pipe, by means of a U-shaped clamp 5,whose two arms extend diametrically and horizontally through the pipeand through grooves in the, side of the inner clip 3, as is indicated inFigs. 2 and 4, and lies in the groove 6, extending centrally andhorizontally about the outer clip 4. The two ends of said U shaped clamparethreaded to receive the nuts '7, whereby the clamping of the parts iseffected. The outer clip 4 is preferably ribbed and cut awayin a mannerwell-known in the'art of metal manufacture, so as to diminishits weight;and the amount of metal used without diminishing its strength. The innerclip 3 has a curved face adjacent to and bearing against the pipe 1 andis so curved as to bear against said pipe at all points. By reason ofthis construction or form said clip has an upper and a lower extensionpartially surrounding the pipe that reaches almost to the verticalcenter thereof, as is shown in Figs. 1 and 5.

Midway between the holes through the pipe 1 for the reception of the twoarms of the U- shaped clamp 5 a vertical slot or groove 8 is made in thesurface of the pipe over which the clip at operates, as is shown clearlyin Figs. 4 and 5 and indicated in Fig. 1. This vertical slot extends inthe form here shown barely through the wall of the pipe. The purpose ofthis groove is to receive the angular vertical edge of the tooth.Therefore in such construction as appears in Figs. 4 and 5 the toothextends through the middle part of the clip 3 and into the notch or slotin the pipe. The function of this slot or notch is to give addedrigidity to the tooth-holding and to cooperate with the clamp 5 inpreventing lateral movement of the tooth. This groove or notch is only apreferable construction and is not needed, because the clamp 5 in itselfwill prevent lateral movement of the tooth; but such arrangement ispreferred in order to obtain absolute rigidity of the tootlrfastening.

Vhile it may seem that the introduction of the four holes for thepassage of the clamp and the addition of the groove or notch 8, if thatbe preferred, would tend to weaken the pipe, such tendency is overcomeby the fact that the clip 3 envelops about half of the pipe and itsextension above and below, coupled with the clamping action of the clampon the round form of the pipe. The fastening, in other words, addsstrength to the pipe that substantially equals the reduction in itsstrength caused by said holes. The chief strain to which said pipe issubjected while the harrow is in use is the torsional strain. It isobserved that with this fastening the strain will be first transmittedto the clips, the bearings being against the lower end of thebearing-face of the inner clip 3 and the upper end of the bearing-faceof the outer clip 4. The strain from the lower part of the inner clip 3is then transmitted to the curved pi pe-surfaee, against which saidlower end of the clip bears and which is imperforate and strong. Thestrain against the upper end of the outer clip is transmitted to theclamp 5, and from said clamp the strain is transmitted to the pipe; butsince said clamp has two arms and extends centrally through the pipe thestrain therefrom to the pipe is Well distributed. This arrangementrenders the fastening device above described extremely more durable andstrong than the construction with which I have heretofore beenacquainted,

wherein the tooth extends vertically and centrally through the pipe, forin this latter arrangement nothing in the fastening tends to overcomethe weakening of the pipe by the introduction of the two large holes forthe reception of the tooth, and the result is a frail structure. Toobtain ample frictional surface in the clips against the tooth, theclips are preferably longer than the diameter of the pipe.

lVhile the drawings and description illustrate my invention in apipe-harrow, I do not limit the invention to a pipe-harrow, as thetooth-fastener shown and described is equally useful in a harrow whereinthe frame-bars are round or partially round and whether solid or hollow,and no change of said fastener is required for harrows having any kindof frame-bars with a curved surface to which it is desired to attach aspike-tooth. Broadly, my invention consists in the means herein setforth for securing a spike-tooth to the curved surface of any frame-barof a harrow.

It is observed that the inner clip 3 tapers centrally, with its sideboundary-lines substantially parallel with the faces of the groove thatreceives the harrow-tooth or with the harrow-tooth when it is in place,whereby said clip at its weakest point is reinforced and of fullstrength.

\Vhat I claim as my invention, and desire to secure by Letters Patent,is

1. A fastener for spike-tooth harrows includin g a clip with a curvedface and two centrally-tapering projections to partially surround thecurved surface of a frame-bar of the harrow and which has a groove inits outer face to receive the tooth, and means for clamping the toothagainst said clip and said clip against the frame-bar.

2. A fastener for spike-tooth harrows including a pair of clips withcorresponding grooves in their adjacent faces to receive the tooth, oneof said clips having a curved face to partially surround the curvedsurface of a frame-bar of the harrow, and means surrounding said clipsfor drawing the clips toward each other and clamping the whole againstthe frame-bar.

3. A fastener for spike-tooth harrows including a pair of clips withcorresponding grooves in their adjacent faces to receive the tooth, oneof said clips having a curved face to partially surround the curvedsurface of etdev s a frame-bar of the harrow, and a clamp that surroundssaid clips and is adapted to extend through the frame-bar of the harrow,whereby the tooth is clamped between said clips and the whole is clampedto the side of the framebar.

4. In a harrow, the combination of a framebar having a curved surface, aclip with a curved inner face partially surrounding the curved surfaceof the frame-bar and having a vertical groove in its outer face, aspiketooth fitting in such vertical groove, and a clamp connected withthe frame-bar and surrounding the tooth, whereby the tooth is heldagainst the clip and the whole secured against the frame-bar.

5. In a harrow, the combination of a f rainebar having a curved surface,a pair of clips with corresponding grooves in their adjacent faces, oneof said clips having a curved face to partially surround the curvedsurface of the frame-bar, a spike-tooth fitting in the grooves betweensaid clips, and means for drawing the clips toward each other andagainst the frame-bar.

6. In a harrow, the combination of afranlebar having a curved surface, apair of clips with corresponding grooves in their adjacent faces, one ofsaid clips having a curved face that partially surrounds the curvedsurface of the frame-bar,- a barrow-tooth fitting in the grooves betweenthe clips, and a clamp that surrounds said clips and extends through theframe-bar, whereby the tooth is clamped between the clips and the wholesecured to the curved surface of the frame-bar.

7. In a harrow, the combination of a framebar with a curved surface, apair of clips with corresponding vertical grooves in their adjacentfaces and with grooves or seats in the sides of said clips, one of saidclips having a curved inner face that partially surrounds the curvedsurface of the frame-bar, a spiketooth fitting in the grooves betweenthe clips, and a staple-like clamp that extends through said frame-barand around said clips fitting in the grooves or seats in the sidethereof, whereby the parts are all clamped together.

8. In a harrow, the combination of a framebar having a curved surface, apair of clips whose length is greater than the diameter of the frame barwith corresponding vertical grooves in their adjacent faces, one of saidclips having a curved inner face that partially surrounds the curvedsurface of the frame-bar, and a clamp that extends around said clips,whereby the parts are clamped together.

9. In a harrow, the combination with a frame-bar having a curved surfaceand a vertical groove in the curved side thereof, a clip having a curvedinner surface that partially surrounds the curved surface of theframebar, and with a vertical groove in its outer face that cuts throughthe curved inner face of said clip, a spike-tooth fitting in the groovein the outer face of the clip, and a clamp about said tooth and clipthat holds them on the frame-bar so that the angular corner of the toothextends through said clip into the groove in the frame-bar, whereby theparts are held in place.

10. In a harrow,the combination with apipe, a pair of clips withcorresponding vertical grooves in their adjacent faces, the inner one ofsaid clips having a curved face that partially surrounds said pipe, aspike-tooth fitting in the grooves between said clips, and astaple-shaped clamping-bolt with its central portion surrounding theclips and its two ends extending centrally through said pipe andthreaded, and nuts on the threaded ends thereof for clamping andcompressing all of said parts together.

In witness whereof I have hereunto affixed my signature in the presenceof the witnesses herein named.

WILLIAM MONROE FRANK.

Witnesses:

M. O. BUCK, V. H. Locxwoon,

